I recently paid around $500 to get my MacBook Air 11 inch fixed because of liquid damage. Part of this was removing the battery and replacing it with a new battery. That was just over a month ago. The other day when I came home from work it wouldn't turn on. Thinking maybe it had died or something I plugged in the charger and it did turn on. However, the battery logo wouldn't show up and it now says that no battery is installed in the power section of 'about this mac.' I have reset the SMC and PRAM, and tried it with another charger to see if that was the problem but it's still the same. Could it be that the person who repaired it used a faulty or old battery? Nothing else would explain it as I have been so careful since having to pay so much to repair it in the first place. It also hasn't died since the repair as I've been careful to charge it when it needs to be to prevent this. When he showed me what he had repaired he showed me that the battery had 0 cycle counts because it was new so I dont know. Thanks for the help. Any help or advice would be great.